Electronic systems are widely used to provide all manner of services to both corporate and consumer markets. Typically, these systems offer services as packages, providing a different level of service to the end customer. Some systems even provide a level of service which is customisable down to the level of an individual user of such systems. This is generally referred to as a service level agreement (SLA). Service providers typically use policy based management so that various kinds of traffic such as voice, data or video receive the priority in terms of bandwidth availability that the respective SLA mandates. Such SLAs therefore require a mechanism for monitoring system activity, policy management and policy enforcement based on this activity.
The activity of monitoring and the act of enforcement require access to the necessary functionality of the components within the system environment. This is a simple issue of integration as access to these components is achieved through open or known proprietary interfaces. However, the task of modelling the instantaneous state of the system in a way that policy enforcement may be executed is not.
Current policy management systems simply take a network element view using a policy decision point server to control the policy enforcement points (routers, switches etc) using access control lists or queue management software.
One such system which takes a network element view is disclosed in U.S. Pat. No. 6,243,747 which discloses a method for enforcing polices for configuration management in communication networks in which a database of models is provided, each model representing a network device and includes attribute values for the parameters of the network device. The method defines network groups and policies for these groups, determines and resolves conflicts between the groups.